Deicing and snow-removing composition, method for producing the same, and use thereof

ABSTRACT

A deicing and snow-removing composition, comprising 30 to 100 parts by weight of calcium oxide (CaO), 5 to 30 parts by weight of magnesium chloride (MgCl2), 3 to 10 parts by weight of calcium chloride (CaCl2), and 0.2 to 2 parts by weight of sodium alginate. A method for preparing such a composition in which the above-mentioned ingredients are combined, gradually heated to 100° C. or higher, and then rapidly heated up to 200° C., and cooled at room temperature.

TECHNICAL FIELD

The present invention relates to a deicing and snow-removingcomposition. More particularly, the present invention relates to a greatimprovement in preventing environmental pollution and vehicle corrosionas well as in deicing and snow-removing, along with the composition.Also, the present invention is concerned with a method for producingsuch a composition and a use of the same.

BACKGROUND ART

Currently, calcium chloride (CaCl₂) is one of the most widely useddeicing and snow-removing agents. With the ability to melt ice andremove snow as well as having the advantage of low cost, calciumchloride is scattered on the roads which are iced or snowed over.

However, calcium chloride is problematic in application to a thick layerof ice or a heap of snow and in the chemical effect it has on iron. Inother words, unless a large quantity of calcium chloride is scattered onthe frozen or snow covered road in winter, a satisfactory thawing effectis not brought about because its deicing or snow-removing ability isinsufficient. On the other hand, if a large quantity of calcium chlorideis scattered, it is ionized so that the abundant chlorine ions thusformed combine with metal ions, especially with Ferric ion (Fe⁺⁺⁺) toproduce FeCl₃, eroding iron structures on the roads, such as vehicles,or various road structures including bridges.

SUMMARY OF INVENTION

Therefore, it is an object of the present invention to overcome theabove problems encountered in prior arts and to provide a deicing andsnow-removing composition which can effectively melt or remove ice andsnow on the roads without producing pollution of the environment andcausing the corrosion of iron structures.

It is another object of the present invention to provide a method forpreparing such a deicing and snow-removing composition.

In accordance with an embodiment of the present invention, there isprovided a composition comprising 30 to 100 parts by weight of calciumoxide (CaO), 5 to 30 parts by weight of magnesium chloride (MgCl₂), 3 to10 parts by weight of calcium chloride (CaCl₂), and 0.2 to 2 parts byweight of sodium alginate, and optionally sand and/or sawdust.

In accordance with another embodiment of the present invention, there isprovided a method for preparing a deicing and snow-removing composition,in which a mixture comprising 30 to 100 parts by weight of calcium oxide(CaO), 5 to 30 parts by weight of magnesium chloride (MgCl₂), 3 to 10parts by weight of calcium chloride (CaCl₂), and 0.2 to 2 parts byweight of sodium alginate are combined, gradually heated to 100° C. orhigher and then rapidly heated up to 200° C., followed by cooling atroom temperature.

DISCLOSURE OF INVENTION

The present invention utilizes an exothermial reaction to water, theheat of which allows the ice and snow over the roads to be thawed orremoved. Calcium oxide (CaO) reacts with water to give calciumhydroxide, producing a heat, as shown in the following chemical formula:

CaO+H₂O→Ca(OH)₂+15.2 kcal

It was found that, when being in contact with snow or ice, calcium oxidecan show a superior deicing and snow-removing effect in a short time byemitting a great heat.

An intensive study of the present inventors on a deicing andsnow-removing composition resulted in the finding that magnesiumchloride (MgCl₂), a highly hygroscopic compound, yields a synergicdeicing and snow-removing effect, in cooperation with calcium oxide.Therefore, the present invention pertains to a deicing and snow-removingcomposition comprising calcium oxide and magnesium chloride incombination with other aids to thaw or melt ice and snow.

The temperature, after the composition of the present invention isscattered, although dependent on the scattered amount of thecomposition, reaches up to approximately 95-105° C., which is enough toshow a superior deicing and snow-removing effect to that of conventionalcompositions.

Calcium hydroxide is used as a useful neutralizing agent for acidicsoil. Hence, when the calcium hydroxide which remains on the road as aresult of the reaction of calcium oxide with snow or ice, soaks throughthe soils near the road, such as arable lands, it may have beneficialinfluence on the neighboring circumstance by alkalifying the soils. Inthe composition of the present invention, calcium oxide is preferablycontained at an amount of approximately 30 to 100 parts by weight. Forexample, if the content of calcium oxide is below 30 parts by weight,the deicing and snow-removing effect is not sufficiently brought about.On the other hand, if too much calcium oxide is used, there occurs aproblem due to an excessive exothermic reaction.

As described above, magnesium chloride (MgCl₂) augments the deicing andsnow-removing effect of calcium oxide owing to its hygroscopic property.It is preferred that ma,gnesium chloride (MgCl₂) amounts toapproximately 5 to 30 parts by weight. For example, if too littlemagnesium chloride is used, an insufficient deicing and snow-removingeffect results. On the other hand, if magnesium chloride is used at anamount larger than 30 parts by weight, it is ionized to form too muchchlorine ions which cause the above-mentioned problem, that is, thecorrosion of vehicles and bridges.

In the composition of the present invention, magnesium chloridehexahydrate (MgCl₂·6H₂O) is usually used, but any kind of magnesiumchloride, including dodecahydrate, octahydrate, tetrahydrate, bihydrateor anhydrate, may be used.

As for the aids to thaw or melt ice and snow, they comprise calciumchloride (CaCl₂) and sodium alginatte in accordance with the presentinvention.

Like magnesium chloride, calcium chloride is a highly hygroscopiccompound, showing a synergic deicing and snow-removing effect, togetherwith calcium oxide. Calcium chloride is preferably added at an amount ofapproximately 3 to 10 parts by weight. For example, if the content ofcalcium chloride is below 3 parts by weight, its deicing andsnow-removing effect is not expressed. On the other hand, if the contentof calcium chloride is above 10 parts by weight, an abundance ofchlorine ion remains on the road, causing the aforementioned problems.

The calcium chloride of the composition of the present invention isusually present in the form of bihydrate (CaCl₂·2H₂O) but may be of anyform, such as anhydrate, monohydrate, tetrahydrate or hexahydrate.

Sodium alginate, a polysaccharide salt, is slowly dissolved in water togive a highly viscous liquid. Because this property has an effect ofpreventing ice from growing, the ice which is re-refrozen from thethawed water when the ambient temperature drops, is not made hard butcrumbly.

It is preferred that sodium alginate is added at an amount ofapproximately 0.2 to 2 parts by weight. For example, if too littlesodium alginate is used, the prevention effect against ice growth isvery insignificant. On the other hand, if the content of sodium alginateexceeds 2 parts by weight, the composition get tangled owing to too highviscosity.

In accordance with another embodiment, sand is added at an amount ofapproximately 30 to 100 parts by weight to the composition, in order toincrease the surface area of the deicing and snow-removing compositionand to prevent vehicles from sliding. Another matter to increase thedeicing and snow-removing effect of the composition, such as saw dust,may be used.

As described above, the components of the composition actsynergistically and complementarily to show an excellent deicing andsnow-removing effect. The water thawed by the composition of the presentinvention is seldom re-frozen to ice when the ambient temperature drops.If the thawed water is frozen, the ice thus formed is not hard butcrumbly, so that the composition of the present invention is veryeffective to deice and remove snow even in the shade or on a road wherethere is little traffic.

When scattered at a proper amount on a region to be deiced orsnow-removed, the composition exhibits an excellent deicing andsnow-removing effect. Commonly, depending on the condition of the ice orsnow, the amount of the composition scattered is determined, but thecomposition of the present invention from half as much as to as much asthe conventional agent, calcium chloride, exhibits a far superiordeicing and snow-removing effect.

The residues of the composition on the road are readily removed by windor passing vehicles and do not produce pollution of the environment.Thus, the composition of the present invention does not cause theproblems accompanied by the use of the conventional snow-removingchemicals.

Therefore, the present invention pertains to the use of the compositionof the present invention in deicing and snow-removing.

Also, the present invention pertains to a method for preparing thedeicing and snow-removing composition. A mixture comprising 30 to 100parts by weight of calcium oxide (CaO), 5 to 30 parts by weight ofmagnesium chloride (MgCl₂), 3 to 10 parts by weight of calcium chloride(CaCl₂), and 0.2 to 2 parts by weight of sodium alginate are mixed,heated to 100° C. or higher and then rapidly up to 200° C., and cooledat the room temperature. Optionally, prior to the heating, sandand/sawdust may be added to the mixture at an amount of approximately 30to 100 parts by weight, in order to increase the deicing andsnow-removing effect.

A better understanding of the present invention may be obtained in lightof following examples which ale set forth to illustrate, but are not tobe construed to limit, the present invention

EXAMPLE I Preparation of a Deicing and Snow-Removing Composition

To a mixture of 80 g of calcium oxide, 15 g of magnesium chloridehexahydrate, 5 g of calcium chloride bihydrate and 0.5 g of sodiumalginate was added 200 g of sand. This mixture was completely mixedtogether, gradually heated up to 100° C. and then, rapidly heated up to200° C., followed by cooling to 10° C. in the ambient atmosphere.

EXAMPLE II Comparison of Deicing Effect

Two ice pieces (A and B), each having a dimension of 20 cm×20 cm×2 cm,were prepared. 500 g of the composition prepared in Example I and 500 gof CaCl₂ were scattered on the Sample Ice A and the Sample Ice B,respectively, and their deicing effects were compared and the resultsare given as shown in Table 1, below.

TABLE I Sample Ice A Sample Ice B Deiced State Completely molten toleave molten on the a small amount of water surface only Time fordeicing 10 min 20 min Temp. just after 98° C. 36° C. scatter

COMPARATIVE EXAMPLE I

In order to clarify the characteristics of the invention, thecomposition (A′) of the present invention according to example I and aconventional chemical (B′) consisting mainly of calcium chloride weretested for chemical properties and snow-removing maintenance ability.

TABLE 2* A′ B′ Temp. just after scatter 95-105  C. 35-40° C. pH at 25°C. 11-12 5-6 Water Solubility (20° C.) good (40-50 g/100 g) very good(70-80 g/100 g) **Residual chlorine ion 1/10 1 Upon Temp. drop after noice or crumbly ice hard ice reformed snow-removing *the data listed inTable 2 may be changed depending on the scattering conditions includingthe amount of snow-removing chemical, weather, snowfall, ice state, etc.**the amount of the residual chlorine ion of the present invention isrelatively expressed on the basis of the amount of the conventionalchemical.

The components in the composition of the present invention organicallyact to bring about a complement and synergic effect in deicing andsnow-removing, so that the composition is far superior to theconventional chemicals in deicing and snow-removing effect. In addition,after being scattered, the composition of the present invention remainsat an amount one-tenth smaller than the conventional chemical, CaCl₂dose. This reduced amount avoids the problems accompanied by theconventional chemical, including corrosion of vehicles and bridges andpollution of the environment. What is better, the composition of thepresent invention is alkaline when it is dissolved in water, so that ithas a beneficial influence on the soils near the region where it isscattered.

The present invention has been described in an illustrative manner, andit is to be understood the terminology used is intended to be in thenature of description rather than of limitation.

Many modifications and variations of the present invention are possiblein light of the above teachings. Therefore, it is to be understood thatwithin the scope of the appended claims, the invention may be practicedotherwise than as specifically described.

What is claimed is:
 1. A deicing and snow-removing composition,comprising 30 to 100 parts by weight of calcium oxide (CaO), 5 to 30parts by weight of magnesium chloride (MgCl₂), 3 to 10 parts by weightof calcium chloride (CaCl₂), and 0.2 to 2 parts by weight of sodiumalginate.
 2. A deicing and snow-removing composition in accordance withclaim 1, further comprising approximately 30 to 100 parts by weight ofsand.
 3. A method for preparing a deicing and snow-removing composition,in which a mixture comprising 30 to 100 parts by weight of calcium oxide(CaO), 5 to 30 parts by weight of magnesium chloride (MgCl₂), 3 to 10parts by weight of calcium chloride (CaCl₂), and 0.2 to 2 parts byweight of sodium alginite are combined, gradually heated to 100° C. orhigher and then rapidly heated up to 200° C., and cooled at roomtemperature.